Pain au Levain

• 13 cup (2 1/2 ounces) mother starter recipe here, cold or at room temperature
• 1 cup plus 2 tablespoons (5 ounces) unbleached bread flour
• 23 cup (3 ounces) whole-wheat flour
• 23 cup (5 4/10 ounces) water, at room temperature
• All of the sourdough starter (16 ounces)
• 1 cup plus 6 tablespoons 11 ounces lukewarm water (about 95 degrees)
• 2 1/4 teaspoons (7 grams) instant yeast (optional)
• 3 1/2 cups (16 ounces) unbleached bread flour
• 2 38 teaspoons (17 grams) salt, or 3 1/2 teaspoons coarse kosher salt

1. Make the sourdough starter.
2. Combine all of the ingredients in a mixing bowl.
3. If using a mixer, mix on the lowest speed using the paddle attachment for 1 minute, then increase to medium speed for about 30 seconds.
4. If mixing by hand, use a large spoon and stir for about 2 minutes, until well blended.
5. The starter should feel dough-like and tacky or slightly sticky; if not, stir in additional flour (if too sticky) or water (if dry) as needed.
6. Transfer the starter to a lightly floured work surface and knead for about 30 seconds.
7. Place it in a clean, lightly oiled bowl, cover the bowl loosely, and leave at room temperature for 6 to 8 hours, until the starter increases to about 1 1/2 times its original size.
8. If you plan to use the starter the same day, allow 1 more hour of fermentation so that it nearly doubles in size.
9. Otherwise, put the starter in the refrigerator for up to 3 days.
10. Make the dough: cut the starter into 10 to 12 pieces and put them in a mixing bowl.
11. Pour in the water, then add the yeast (if using) and mix with the paddle attachment on the lowest speed or by hand with a large spoon for about 1 minute to soften the starter.
12. Add the flour and salt.
13. Switch to the dough hook and mix on the lowest speed, or continue mixing by hand, for 3 minutes, to form a coarse ball of dough that's very tacky and slightly warm.
14. Let the dough rest for 5 minutes.
15. Resume mixing on medium-low speed for 3 minutes more or knead by hand for 3 minutes, adding more flour or water as needed to make a soft, supple and tacky by not sticky ball of dough.

starter, flour, flour, water, starter, water, yeast, flour, salt

Taken from cooking.nytimes.com/recipes/1014026 (may not work)